How Many mg of THC Are in My Homemade Edible? (60-Second Math)

Quick answer: Multiply your flower weight in grams by 1000, by your THC percentage as a decimal, by your extraction efficiency (use 0.75 for stovetop, 0.85 for slow cooker, 0.90 for Ardent or alcohol). That's total mg in your batch. Divide by carrier volume (ml) to get mg/ml potency. Multiply that by ml used in the recipe and divide by servings to get mg per serving.

Most online calculators ask for inputs you don't have and spit out one suspiciously precise number. Here's the actual two-equation system used by the BeTheHippy calculator — once you understand it, you can sanity-check any edible recipe in 60 seconds.

Equation 1: Total mg in your infusion

flower_grams × 1000 × THC_percent × extraction_efficiency = total_mg

Example: 7g of 20% THC flower, slow-cooker butter (assume 80% efficiency):
7 × 1000 × 0.20 × 0.80 = 1,120 mg total THC

Equation 2: mg per serving

(total_mg ÷ carrier_ml) × ml_used_in_recipe ÷ servings = mg_per_serving

Example continued: 1,120 mg in 240 ml (1 cup) of butter, used 2 tbsp (29.6 ml) in a 12-brownie recipe:
(1,120 ÷ 240) × 29.6 ÷ 12 = 11.5 mg per brownie

Why You Should Always Round Down

The "75–90% extraction" range is real. If your butter actually hit 90% efficiency and you assumed 80%, your brownies are 12% stronger than the calculator says. Always use the lower-end efficiency number when calculating, and treat the result as the maximum likely dose, not a precise number. Then dose-test.

The Beginner-Safe Way

For anyone new to edibles: target 2.5 mg per serving. To get there from 7g of decent flower, dilute the math — make a stronger butter (small batch, 1 stick) and use only ½ tablespoon in your recipe, or make a weaker butter and use the full amount. Either path lands you at a safe starting dose with built-in margin for error.

Frequently Asked Questions

What's a realistic extraction efficiency to assume?+

75% is the safe default for stovetop butter or oil with a lid on. Slow cookers run 75–85%. The Ardent FX and alcohol-based tinctures hit 85–95%. If you don't know, use 75% — you'd rather your edible be slightly stronger than expected than weaker.

Do I really need a kitchen scale?+

Yes. Eyeballing 7g of flower is the single biggest source of dosing error. A $15 0.1g jewelry scale is the minimum tool that makes any of this math meaningful. Without it you're guessing within ±50%.

How do I find the THC percentage of my flower?+

Dispensary flower is on the label or COA (certificate of analysis). Homegrown without lab testing is unknowable — assume 12–18% as a conservative estimate. Avoid premium pricing strains assumptions; old or poorly stored flower is often half the labeled number.

Why does my friend's batch hit harder than mine with the same recipe?+

Three usual suspects: their flower is fresher, their decarb was more thorough, or they cooked at a steadier temperature. Same recipe ≠ same potency unless inputs and process are identical.

Can I just buy lab-tested distillate and skip all this?+

Yes, and the math is much simpler — distillate ships with a known mg/ml and you just divide by servings. But you give up the ability to use flower you already have and the cost ramps up.

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